SOURCE ROCK CHARACTERIZATION AND CORRELATION BASED ON GEOCHEMICAL METHODS IN SANGKAREWANG FORMATION, OMBILIN BASIN

• Main Author: Beladina Azis, Chika
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/55331
• Institution: Institut Teknologi Bandung

Hydrocarbon exploration activities rely heavily on geochemical analysis as an initial step in determining the potential source rock in a sedimentary basin. This study aims to analyze the source rock in the Sangkarewang Formation, Ombilin Basin. The analysis includes characterization of the source rock to determine the quantity of organic material, the maturity of the organic material, and the type of organic material, as well as biomarker analysis and geochemical correlation between source rock and oil sample. The analysis has been done to 68 samples composed of 67 source rock samples (from 2 wells and 7 outcrop samples) and 1 oil sample from Pusat Sumber Daya Mineral, Batubara dan Panas Bumi (PSDMBP). The source rock samples were then validated with total organic carbon (TOC) and S2 values resulting in only 12 source rock samples. The characterization result of the source rock showed that the source rock sample of the Sangkarewang Formation is potential that has very good to excellent quantity with types of kerogen I and II which are capable to produce oil or condensate, and had a maturity level early mature. Based on biomarker analysis, the source rock sample of the Sangkarewang Formation is composed of a mixture of organic material from algae and higher plants and has a lacustrine depositional environment with suboxic to oxic conditions. The oil samples were then correlated with the source rock based on the similarity in the characteristics of the biomarkers. The correlation results indicate that the oil samples have a positive correlation with the source rock samples of the Sangkarewang Formation which were deposited in oxic environment. Therefore, the oil sample can be interpreted to have originated from the oxic part of the Sangkarewang Formation.